Ladle carriage, particularly for converters in steel mills



Dec. 28, 1965 w, GRUNEWALD ET AL 3,225,397

LADLE CARRIAGE, PARTICULARLY FOR CONVERTERS IN STEEL MILLS 2Sheets-Sheet 1 Filed March 21, 1962 3 7 l T I Iii FIT L I Q a NN MN T AR Jnven fora: bajdem g buutaaald Dec. 28, 1965 w. GRUNEWALD ETAL3,225,397

LADLE CARRIAGE, PARTICULARLY FOR CONVERTERS IN STEEL MILLS 2Sheets-Sheet 2 Filed March 21, 1962 /IIIIIIlI/l United States Patent 1Claim. in. 22-s2) Our invention relates to ladle carriages, particularlyfor receiving steel from converters in steel mills.

After blowing of a converter, the steel is poured into a ladle which, bymeans of the ladle carriage, is kept close to the mouth of the tiltingconverter. The filled ladle is transported on the carriage to thefoundry where the ladle is transferred to a crane or directly emptiedthrough a bottom opening into the ingot moulds.

It is an object of our invention to provide a ladle carriage that, asidefrom being applicable in the same manner as the known ladle carriages,can also be used for other purposes.

Another object of the invention is to devise a ladle carriage thataffords more accurately adapting the varying ladle position to thetilting motion of the converter while the steel is being poured into theladle.

Still another object of our invention is to devise an improved ladlecarriage that affords reducing the pouring distance as well as thedanger of spilling and splashing to a greater extent than heretoforefeasible with known ladle carriages.

A ladle carriage according to the invention is based upon the knowndesign in which the free end of an outrigger boom serves to hold theladle, and the outrigger can be moved in such a manner that the ladle,during emptying of the converter, follows approximately the path of theconverter mouth. According to our invention, however, such an outriggerboom is designed as a double-armed lever and is mounted for motion withtwo degrees of freedom of which the first one affords a ladle motion inadaptation to the tilting of the converter, while the second degree offreedom permits an essentially vertical displacement of the ladleindependent of the tilting of the converter. Among the advantages thusachieved is the fact that the filled ladle, instead of being transportedto the foundry on the heavy ladle carriage, can be put upon a simplerail vehicle which then takes care of further transportation. Thisreduces the necessary number of the heavy and expensive steel-receivingladle carriages and also reduces the time required for transporting thesteel from the converter to the foundry.

In known ladle carriages the movement of the outrigger boom duringfilling of the ladle is adapted to the tilting motion of the converteronly in a coarse way, so that the purpose of such adaptation, namely tokeep the pouring distance as short as possible and to minimize splashingor spilling of steel, is met only incompletely. These shortcomings arevirtually eliminated by a ladle carriage according to the invention inthat the outrigger lever is longitudinally displaceable relative to itsfulcrum and has its rear arm guided along a guiding contour duringlongitudinal displacement.

Since the guiding contour can be given any desired shape, the path ofthe ladle can be better adapted in this manner to the converter tiltingmotion so that the purpose of such adaptation is satisfied to an optimalextent.

According to another, preferred feature of our invention, theabove-mentioned guiding contour is constituted by the longitudinal sideof a guiding slot. This provides a support for the rear end of theoutrigger boom and 3,225,397 Patented Dec. 28, 1965 thereby prevents itfrom tilting upwardly under its own weight when the boom is withdrawninto the carriage after the ladle is put off.

According to another, more specific feature of the invention, thefulcrum of the outrigger lever is preferably made displaceable in thevertical plane for producing the outrigger motion in accordance with theabove-mentioned second degree of freedom.

The displaceability of the outrigger boom relative to a support thatforms the fulcrum can be used to further advantage by giving the loweredge of the boom a cam curvature that coacts with the above-mentionedcontour at the rear end of the outrigger boom in producing the motionaccording to the first degree of freedom. The advantage of thusdistributing the cam action upon two contours is the fact that thecurvature of the contour at the rear end can be kept considerablysmoother and shallower than if this contour were alone effective, whilethe curvature of the lower edge of the boom is likewise only slight.

Because of the considerable width of the outrigger boom, the guidance atits rear end is preferably subdivided into two individual guidanceportions. Since the same applies to the support of the outrigger at thefulcrum, the design may result in a statically indeterminate four-pointsupport which may become objectionable in view of the heavy loads to becoped with. This, however, can be remedied by interconnecting the twoindividual supports that jointly define the fulcrum axis so as to form amechanical or hydraulic balancing system;

The foregoing and more specific features of our invention will be morefully apparent from the following description in conjunction with theembodiments of ladle carriages according to the invention illustrated byway of example on the accompanying drawings in which:

FIG. 1 is a lateral view of the ladle carriage shown during emptying ofsteel from a converter into a ladle.

FIG. 2 shows in its left portion a section along the line AA and in itsright portion a section along the line BB in FIG. 1; and

FIG. 3 illustrates another embodiment of a ladle carriage by a sectioncorresponding to the left portion of FIG. 2.

The illustrated ladle carriage comprises a frame structure 1 withlateral walls 2 and a counterpoise 3 for compensating the load. Theframe structure 1 is rotatable about a vertical axis on a truck 4 whosewheels 5 run on rails 6. The required propulsion drive and the drive forrotating the frame structure about the vertical axis are not illustratedbecause they are not essential to the invention and known as such. Anoutrigger boom 7 protrudes from the right of the frame structure 1 (FIG.1). A portion of the boom 7 extends transversely between the two lateralwalls 2 (FIG. 2) and is formed by several boxprofile structures partlyvisible in FIG. 2. The free end 8 of the outrigger 7 is designed as afork whose legs straddle a casting ladle 9. Two hooks 10 at the ends ofthe legs engage from below the respective trunnions 11 with which theladle is conventionally provided.

Journalled on the rear end 12 of the outrigger 7 are two laterallyprotruding rollers 13 which are located in guide slots 14 of therespective side walls 2. The lower edge 15 of the outrigger 7 rests upontwo roller pairs 16, 17. Each pair of rollers is journalled on a smallteeter member 18. The purpose of using roller pairs is to reduce thearea pressure. Carriages of lower weight may be equipped with singlerollers in which case the teeter members 18 are omitted. In theillustrated embodiment, each teeter 18 is pivoted on a lever 19rotatable about a pivot 20 on frame structure 1.

The piston 21 of a hydraulic drive has its head 24 articulately joinedwith the outrigger boom 7. The ap pertaining hydraulic cylinder 22 islocated centrally between the lateral walls 2 and is tiltably mounted at23 on the frame structure 1. The hydraulic drive has a doubleactingdesign and serves to displace the boom 7 longitudinally on the rollerpairs 16, 17. Two further hydraulic drives serve for rotating therespective levers 19. The appertaining hydraulic cylinders 25 arepivotally attached at 26 to the frame structure 1, and the respectivepistons 27 are connected with the levers 19 by respective links 28. Thetwo cylinders 25 are hydraulically connected in parallel. This isindicated in FIG. 2 by a pressure line 29 interconnecting the twocylinders 25.

In operation, the ladle carriage is run to the location of a converter30 to be emptied, with the outrigger boom 7, carrying an empty ladle 9,withdrawn into the carriage. With the carriage in proper position, theconverter 30 is tilted about the axis of its trunnions 31 after theblowing operation is terminated. The pouring of the steel commences whenthe converter assumes the dot-and-dash position. For this purpose theboom 7 is placed in the position where the ladle edge and ladle trunnionare at the respective locations denoted by I. With increasing tiltingangle of the converter, the boom 7 is run out of the carriage a furtherextent so that the ladle passes successively through the positions II,III, IV and ultimately reaches the end position V. The dot-and-dashcurves denoted by x and y indicate the travel path of the edge 32 at theconverter mouth 33 and of the ladle edge 34 respectively. It will berecognized from these paths that the ladle accurately follows thetilting motion of the converter mouth.

The path 3 is obtained by giving the upper edge 35 of slot 14- asuitable guiding contour and also applying a corresponding guidecurvature to the lower edge on the boom 7. If only one of these twoexpedients were used, considerably steeper curvatures either at edge 35or at edge 15 would result and would cause correspondingly unfavorablestresses and strains.

When the ladle 9 is filled and the converter 30 tilted back to its baseposition, the boom 7 is withdrawn into the carriage and the framestructure 1 is turned 90 about the vertical axis. The carriage can newtravel on rails 6 away from the converter, for example to another railon which a simple platform car is available for further transportationof the ladle. For lowering the ladle onto the vehicle, the boom 7 is runout for moving the ladle to above the car. Then the boom 7 is lowered byrotation of the levers 19 with the aid of the drives 25, 27, until theladle is set upon the platform of the car and the hooks 10 have releasedthe ladle trunnions 11. Thereafter the boom 7 can be moved back into theladle carriage. The guide slots 14 then prevent the boom from turningupwardly under its own weight. While the ladle is being transported awayon a separate, simpler vehicle, the ladle carriage is again ready toreceive an empty ladle and can travel to another converter to bedischarged.

The hydraulic parallel connection of the two cylinders has the action ofa balancing system which causes the two rails 36, by means of which theboom 7 rests upon the respective two pairs of rollers 16 and 17, toalways impose equal forces upon these rollers. The outrigger boom 7 isthus supported in a statically definite manner.

The same effect can be obtained according to FIG. 3 by purely mechanicalmeans with the aid of a balance lever 37 which is pivotally mountedbetween bearing blocks 38 on a pivot pin 39 in frame structure 1. Thelevers 19 are connected with the respective ends of the balancing lever37 by means of cross-type universal joints 40, each permitting apivoting motion about two axes perpendicular to each other. Forsimplicity, only one supporting roller 41 is provided on each side. Somedifliculty is encountered with respect to design and space requirementsof the universal joints 40 which must be given large dimensions becauseof the very great forces involved. For that reason a hydraulic balancingsystem as exemplified by FIG. 2 is preferable in most cases.

The purpose of the levers 19 is not limited to affording a filled ladle9 to be put off the outrigger boom by lowering the latter or converselyto load an empty ladle onto the boom. These levers 19 also permitadjusting and displacing the path y of the ladle edge. This may becomenecessary or desirable if converters of different dimensions are to beserviced by the same ladle carriage in the same plant, and also if thepath x has changed by material burning away from the converter spout.

While we have described the invention with reference to converters insteel mills, ladle carriages according to the invention are alsoapplicable to advantage in other plants requiring molten metal to bepoured from a containing vessel structure into a casting ladle bytilting the vessel structure, such as the pouring of aluminum or otherlight metal from a tilting crucible into a ladle from which the metal iscast into moulds. In such cases, too, the invention affords keeping thepouring distance uniformly short and preventing or greatly minimizingthe danger of spilling or splashing, aside from permitting a greaterversatility of ladle motion for other purposes.

To those skilled in the art it will be obvious from a study of thisdisclosure that our invention permits of varying modifications withrespect to details and hence can be given embodiments other thanparticularly illustrated and described herein, without departing fromthe essential features of our invention, and within the scope of theclaim annexed hereto.

We claim:

A ladle carriage for converters in steel plants and similar purposes,comprising a wheeled truck and a frame structure thereon, said framestructure having fixed guide means forming a guide contour extending ina given direction, roller means engaging with said guide means andguidingly displaceable along said contour, a rigid boom forming adouble-armed lever extending generally in the given direction of saidcontour, said lever having an arm fulcrummed on said roller means inguided relation with said contour and being displaceable with saidroller means relative to said frame structure in the given direction ofsaid contour, said lever also having a bifurcated frontal arm protrudingbeyond said frame structure and having two legs for straddling a ladleand adapted at the respective leg ends to hold the ladle, two supportingrollers engaging each of said respective legs from below and beingarranged behind each other longitudinally of said lever, a teeter memberon which said two rollers are journalled, an arm member pivotally joinedwith said teeter member and pivotally mounted on said frame structurefor raising and lowering said rollers, and balancing meansinterconnecting the teeter members associated with each leg for conjointload-sharing operation of said legs.

References Cited by the Examiner UNITED STATES PATENTS 1,629,184 5/1927Thomas 2282 2,292,599 8/1942 Batie 2282 2,892,225 6/1959 Buhrer et al22-82 FOREIGN PATENTS 665,205 4/ 1929 France.

743,000 1/1933 France.

614,338 6/1935 Germany.

I. SPENCER OVERHOLSER, Primary Examiner.

MARCUS U. LYONS, MICHAEL V. BRINDISI,

Examiners.

